Flowmaster 4" System

[Ncostello]

Flowmaster has a complete 4" system including the downpipe, muffler and all welded on hangers. They also have a sound clip on a 3500 2nd gen and it sounds great!



The muffler is a "modified" 50 series unit with 4" in/out fittings.



According to them, the system works great on the Ram Cummins. Any thoughts on this setup versus a straight thru muffler setup?



I've got a thread going on the Magnaflow but wanted to ask about this setup in a different thread for future search purposes.

 

[azpete]

Just installed one on mine last weekend. It's just alittle quieter than the old stock with just the resonator. It has a nice sound thats not to anouying and haven't noticed any drone. easy install too.

 

[lmills]

Any thoughts on this setup versus a straight thru muffler setup?

I like Flowmasters, but for a turbo application I would take a straight thru muffler any day over a chambered muffler

 

[TSchuetz]

Flowmaster has a complete 4" system including the downpipe, muffler and all welded on hangers. They also have a sound clip on a 3500 2nd gen and it sounds great!



The muffler is a "modified" 50 series unit with 4" in/out fittings.



According to them, the system works great on the Ram Cummins. Any thoughts on this setup versus a straight thru muffler setup?



I've got a thread going on the Magnaflow but wanted to ask about this setup in a different thread for future search purposes.

I have not been impressed with the durability of the Flowmaster product in the "rust belt". While the price of the system may be more appealing, youmay want to consider stainless from a number of suppliers. I guess it all depends on when you use your truck and how long you intend to own it.



Tim

 

[Forrest Nearing]

I like Flowmasters, but for a turbo application I would take a straight thru muffler any day over a chambered muffler

very good advice!!!!



flowmasters are designed to take advantage of exhaust pulses to cancel sound, and the pulses hitting the divider plates cause eddies in the current... that's fine in a non-turbo application, but the turbine chops up those exhaust pulses and blends them into a steady stream flow... those dividers and the eddies in the current create major turbulence and really hurt exhaust flow!!!



on a 400-500hp small block w/ 2. 5" dual exhaust, going from a pair of flowmasters to a "turbo friendly" (straight through/constant flow) muffler will pick up ~10% horsepower!!!!! that's a CONSIDERABLE difference!!!!



the turbo also spools up quicker, etc. etc.



I have nothing against flowmaster products or chambered mufflers in general... I use MAC chambered mufflers on all my non-turbo gasser hot rods... fairly similar product to flowmasters. but I would NEVER use them on a turbo application!!!



Forrest

 

[Ncostello]

If 1000HP big block drag cars are running Flowmaster exhaust at the strip... why would they choose something that creates major exhaust turbulence and really hurts exhaust flow? Isn't their special design for reducing flow restriction to a bare minimum?



The upstroke of the pistons are shoving out the spent gasses... and that flow is passing through the turbo thus spinning the wheel. The gasses are then further pushed out the tail pipe by the piston exhaust stroke. They turbo is not doing anything so to speak to assist the exhaust flow. Its spinning or driven because of it. Its collecting the flow for mechanical force in the shaft to turn the intake blades.



Flowmaster is saying their system offers free flow characteristics because of design. Their sound byte sure sounds pretty good too. Just curious here because on an exhaust stroke the boost means nothing inside the diesel... right. I'm pretty sure I've seen turbo gasser drag cars run Flowmasters.

 

[Forrest Nearing]

those big block dragsters are not turbocharged... chambered mufflers work fine with non-turbocharged applications...



the turbine is spinning because of the exhaust flow, but it also takes the brunt of the exhaust pulses and what you get after the turbine is a steady stream of exhaust... hold your hand at the tailpipe of a non-turbo vehicle, and you'll feel the pulses hitting your hand... do the same for a turbo vehicle, and it's just a steady stream...



the flowmasters are designed to make use of those exhaust pulses... when those pulses are not present, the eddies caused by the plates cause a lot of turbulence... w/ exhaust pulses present, those eddies disipate before they cause a major problem.



you can believe what you want, but I've personally seen a 420rwhp turbocharged SBF pick up 45rwhp to 465 on the dyno with no other changes but swapping out the flowmasters for a straight through muffler design. the turbos also spooled up a good deal quicker.



why do big trucks that have plenty of room for huge mufflers use straight through mufflers if chambered mufflers are a superior design?



if you've seen turbo gasser drag cars run Flowmasters, it's because they're sponsored... Joe Morgan's turbo pinto ran a Borla for YEARS... he switched over to a Flowmaster when they started waving money at him... the car dropped off slightly, but he was able to afford to make it go faster w/ the money



Forrest

 

[lmills]

Ncostello

"They turbo is not doing anything so to speak to assist the exhaust flow. Its spinning or driven because of it. Its collecting the flow for mechanical force in the shaft to turn the intake blades. "



Yeh but the point your missing is that the chambered muffler causes added backpressure on the turbo whih cuases it to spool slower. Backpressure is great on a gasser. The want to retain higher cylinder pressures to increase more power. We get or cylinder pressure from the turbo.



"Flowmaster is saying their system offers free flow characteristics because of design. Their sound byte sure sounds pretty good too. "



Yeh and the poeple selling magnets and fuel turbulators say they work great also.



Just curious here because on an exhaust stroke the boost means nothing inside the diesel... right. I'm pretty sure I've seen turbo gasser drag cars run Flowmasters.

Don't take our word for it, I only ran one for 6 months then kicked it to the curb. Go to a website for cars like grand nationals and ask the pro's what they run on their turbo charged grand nationals. I'll bet you wont find too many running a flowmaster.

 

[Ncostello]

Then the stock muffler Dodge uses is most likely much worse than any flowmaster could ever be? I can't even remember what mine looked like. I've ran a straight pipe the whole time I've had it.



Big Rig truck mufflers... are they packed with stainless steel wool or fiberglass like the performance straight thru's for our trucks?

 

[Forrest Nearing]

the stock muffler is probably worse than a flowmaster, but if you're going to be spending money on an aftermarket muffler, why not buy a cheaper one that flows better?

 

[Ncostello]

I'm just undecided on what to get. I dont want to have to buy something twice especially when it costs 400-700.



I have not ruled out any system or muffler. I'm really looking for good sound control. The straight pipe has been fun but I'm starting to look for a quieter truck now and I don't wanna get a system thats only marginally quieter than a straight pipe.



Perhaps if I use two straight thru mufflers I'd get quiet and performance. I searched and found some using a 20" magnaflow and a 18" magnaflow together with good results.



Or maybe a OEM resonator and a Magnaflow system (or comparable). Thanks for the input.

 

[24V-DSL]

Neil... .



Call Rip Rook. He really knows a lot about sound characteristics of the different mufflers and systems.



866. 211. 1533

 

[Ncostello]

Called Rip Rook. Can't begin to describe how helpful and knowledgable the guy is. Thanks 24V-DSL!

 

[24V-DSL]

Neil...

You're welcome.



I'm headed for the Woodburn Ore. Truck Drags tommorrow morning. Hope to see Rip break into the 11's.